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991.
Tomoya Saito Hiroshi Kakehi Yoshihiro Kato Masashi Miura Norifumi Isu Hideo Sawada 《先进技术聚合物》2013,24(6):532-540
Calcium chloride reacted with sodium carbonate in the presence of a variety of fluoroalkyl end‐capped oligomers such as fluoroalkyl end‐capped acrylic acid oligomer (RF‐[ACA]n‐RF), 2‐methacryloyloxyethanesulfonic acid oligomer (RF‐[MES]n‐RF), N,N‐dimethylacrylamide oligomer (RF‐[DMAA]n‐RF) and acryloylmorpholine oligomer (RF‐[ACMO]n‐RF) to afford the corresponding fluorinated oligomers/calcium carbonate composites. Each fluorinated oligomer/calcium carbonate composite thus obtained is nanometer size‐controlled very fine particles (25–114 nm) possessing a good dispersibility and stability in a variety of solvents including water. Thermal stability of these fluorinated calcium carbonate nanocomposites was studied by thermogravimetic analyses measurements. Fluorinated oligomes, in which the theoretical oligomer content in the composites is 19%, were able to give no weight loss corresponding to the content of oligomer in each case even after calcination at 800 °C. On the other hand, a slight weight loss corresponding to the contents of oligomers in the composites after calcination at 800 °C was observed in RF‐(MES)n‐RF/, RF‐(DMAA)n‐RF/ and RF‐(ACMO)n‐RF/calcium carbonate nanocomposites, in which the theoretical contents of the oligomers were 36–53%, although RF‐(ACA)n‐RF/calcium carbonate nanocomposites gave a clear weight loss corresponding to the contents of oligomer under similar conditions. Fluorinated oligomers/calcium carbonate nanocomposites possessing no weight loss at 800 °C were applied to the surface modification of poly(methyl methacrylate) (PMMA) to exhibit a good oleophobicity imparted by fluorines on the surfaces. Interestingly, these fluorinated calcium carbonate nanocomposites after calcination at 800 °C were found to exhibit the similar oleophobic characteristic on the modified PMMA surfaces as well as that of the nanocomposites before calcination. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
992.
Yongbing Shen Goulven Cosquer Hiroshi Ito David C. Izuogu Alex J. W. Thom Toshiaki Ina Tomoya Uruga Takefumi Yoshida Shinya Takaishi Brian K. Breedlove Zhao‐Yang Li Masahiro Yamashita 《Angewandte Chemie (International ed. in English)》2020,59(6):2399-2406
The first three‐dimensional (3D) conductive single‐ion magnet (SIM), (TTF)2[Co(pdms)2] (TTF=tetrathiafulvalene and H2pdms=1,2‐bis(methanesulfonamido)benzene), was electrochemically synthesised and investigated structurally, physically, and theoretically. The similar oxidation potentials of neutral TTF and the molecular precursor [HNEt3]2[M(pdms)2] (M=Co, Zn) allow for multiple charge transfers (CTs) between the SIM donor [M(pdms)2]n? and the TTF.+ acceptor, as well as an intradonor CT from the pdms ligand to Co ion upon electrocrystallisation. Usually TTF functions as a donor, whereas in our system TTF is both a donor and an accepter because of the similar oxidation potentials. Furthermore, the [M(pdms)2]n? donor and TTF.+ acceptor are not segregated but strongly interact with each other, contrary to reported layered donor–acceptor electrical conductors. The strong intermolecular and intramolecular interactions, combined with CT, allow for relatively high electrical conductivity even down to very low temperatures. Furthermore, SIM behaviour with slow magnetic relaxation and opening of hysteresis loops was observed. (TTF)2[Co(pdms)2] ( 2‐Co ) is an excellent building block for preparing new conductive SIMs. 相似文献
993.
Toshihide Taniguchi Mitsutaka Imoto Motonori Takeda Takeo Nakai Masatoshi Mihara Toshiyuki Iwai Takatoshi Ito Takumi Mizuno Akihiro Nomoto Akiya Ogawa 《Heteroatom Chemistry》2015,26(6):411-416
A new method for the hydrolysis of diazonium salts, without the formation of tar, was developed. A two‐phase system consisting of cyclopentyl methyl ether (CPME) and water is very effective for the hydrolysis of diazonium salts. Using this solvent system, the diazonium salt prepared from 3‐(4‐nitrophenoxy)aniline gave 3‐(4‐nitrophenoxy)phenol in high yield (96%) within 20 min. The synthesized phenol is an industrially important raw material in polymer syntheses. Furthermore, the use of the present two‐phase system of CPME and water successfully brought about the efficient conversions of several m‐substituted anilines into the corresponding m‐substituted phenols. This is the first example of hydrolysis of diazonium salts using the two‐phase system (CPME and water). 相似文献
994.
Sujuan Guo Takahumi Ogasawara Tomoya Saito Hiroshi Kakehi Yoshihiro Kato Masashi Miura Norifumi Isu Hideo Sawada 《Colloid and polymer science》2013,291(12):2947-2957
Fluoroalkyl end-capped vinyltrimethoxysilane oligomer/anatase titanium oxide nanocomposite-encapsulated low molecular weight aromatic compounds [RF-(VM-SiO2)n-RF/an-TiO2/Ar-H] were prepared by the sol–gel reactions of the corresponding oligomer in the presence of anatase titanium oxide nanoparticles (an-TiO2) and the aromatic compounds such as bisphenol A [BPA], 1,1′-bi(2-naphthol) [BINOL], and fullerene under alkaline conditions. Thermogravimetric analyses measurements show that RF-(VM-SiO2)n-RF/an-TiO2 nanocomposite-encapsulated BPA and BINOL, in which the theoretical contents in the composites are 25?~?32 %, were found to give no weight loss corresponding to the contents of these aromatic compounds even after calcination at 800 °C. On the other hand, the corresponding nanocomposite-encapsulated fullerene exhibited weight loss behavior related to the presence of fullerene under similar conditions; however, UV–vis spectra showed the presence of the residual fullerene in the composites even after calcination. An-TiO2 in these fluorinated nanocomposites can keep its crystalline structure without phase transformation into rutile even after calcination at 1,000 °C, although the parent an-TiO2 nanoparticles underwent a complete phase transformation into rutile under similar conditions. Notably, RF-(VM-SiO2)n-RF/an-TiO2/Ar-H nanocomposites can give a good photocatalytic activity even after calcination at 1,000 °C for the decolorization of methylene blue under UV light irradiation. More interestingly, these fluorinated nanocomposites before and after calcination were found to exhibit a higher photocatalytic activity at the initial UV light irradiation from 1 to 3 min than that of the corresponding RF-(VM-SiO2)n-RF/an-TiO2 nanocomposites under similar conditions. Figure
Encapsulated BPA and BINOL in the nanocomposites exhibit no weight loss even after calcination at 800 °C, and RF-(VM-SiO2)n-RF/an-TiO2/Ar-H nanocomposites before and after calcination at 1,000 °C can give a higher photocatalytic activity than that of RF-(VM-SiO2)n-RF/an-TiO2 nanocomposites. Notably, the photocatalytic activity of RF-(VM-SiO2)n-RF/an-TiO2/C60 nanocomposites after calcination increased by about 2.5-fold, compared with that of RF-(VM-SiO2)n-RF/an-TiO2 nanocomposites. 相似文献
995.
Hiroaki Otaka Shigeru Ogawa Ichiro Minato Hisayoshi Utsugi Takashi Amagai 《International journal of environmental analytical chemistry》2013,93(8):583-599
The extractability of dioxins from suspended substances (SS) in distributed water was evaluated. Dioxins adsorbed on the collected SS were extracted by pressurized liquid extraction with various solvents. High-polarity solvents (acetone, alcohols) extracted considerably higher amounts of some lower-chlorinated dibenzo-p-dioxins (LoCDDs) than did low-polarity solvents (dichloromethane, toluene), whereas the extracted amounts of higher-chlorinated dibenzo-p-dioxins (HiCDDs) were roughly the same, regardless of the solvent. The extractability of the LoCDDs depended on the isomer. Daily variations in quantities for PCDDs, organic matter (OM), and iron in the SS were examined, and the results suggested that in the SS, LoCDDs and HiCDDs were associated, respectively, with raw water-derived organic matter and microparticles sequestered in iron oxy(hydr)oxide floc. It was also suggested that the low extractability of certain congeners was not attributable to the enormously coexisting ferric compounds but was probably attributable to OM with which they strongly associate. 相似文献
996.
Makoto Kiso Yuji Ogawa Yushun Fujishima Minoru Fujita Shinji Tanaka Akira Hasegawa 《Journal of carbohydrate chemistry》2013,32(4):625-638
Abstract In order to elucidate further the relationship between the composition of the fatty acyl groups in the nonreducing-sugar subunit of bacterial lipid A and its biological activity, 3-O-[(3R)-3-(acyloxy)tetradecanoyl]-2-deoxy-2-[(3R)-3-hydroxytetradecanamido]-4-O-phosphono-D-glucose [GLA-63(R, R) and GLA-64(R, R)], and 3-O-[(3R)-3-(acyloxy)tetradecanoyl]-2-deoxy-4-O-phosphono-2-tetradecanamido-D-glucose [GLA-67(R), GLA-68(R) and GLA-69(R)] have been synthesized. Benzyl 2-[(3R)-3-(benzyloxymethoxy)tetradecanamido]-2-deoxy-4,6-O-isopropylidene-β-D-glucopyranoside (5) and benzyl 2-deoxy-4,6-O-isopropylidene-2-tetradecanamido-β-D-glucopyranoside (6) were each esterified with (3R)-3-dodecanoyloxytetradecanoic acid (1), (3R)-3-tetradecanoyloxytetradecanoic acid (2) or (3R)-3-hexadecanoyloxy-tetradecanoic acid (3), to give 7-11, which were then transformed, by the sequence of deisopropylidenation, 6-O-tritylation and 4-O-phosphorylation, into a series of desired compounds. 相似文献
997.
Akira Hasegawa Takatoshi Murase Masayuki Ogawa Hideharu Ishida Makoto Kiso 《Journal of carbohydrate chemistry》2013,32(4):429-439
ABSTRACT 7-O-, 7,9-Di-O-, and 7,8,9-tri-O-acetyl derivatives of N-acetyl-neuraminic acid were synthesized starting from benzyl [2-(trimethylsilyl)-ethyl 5-acetamido-3,5-dideoxy-8,9-O-isopropylidene-D-glycero-α-D-galacto-2-nonulopyranosid]onate (1). 相似文献
998.
We analyze the dynamics of a microscale liquid surface interacting with a time-dependent electrostatic field. The analysis is based on Hamilton’s theory, which can deal with electrodynamics as well as mechanics. The analysis predicts that the mass of a liquid interacting with an electrostatic field is reduced as a result of its motion. The mass reduction occurs through the formation of a high-aspect liquid meniscus, which is eventually transformed to a molecular flow of the liquid. The high-aspect liquid meniscus is used to erect a CNT on the glass surface, and the molecular flow is used to initiate a plasma-induced reaction that produces a hydrogen-storing polymer. 相似文献
999.
QianMing Wang Keishiro Ogawa Kazunori Toma Hitoshi Tamiaki 《Journal of photochemistry and photobiology. A, Chemistry》2009,201(2-3):87-90
A luminescent hydrogel was successfully prepared by immobilizing an europium(III) tetrakis(β-diketonate) complex into a gallate-based hydrogelator. The Eu(III) emission in hydrogel media was switched reversibly “on-off” as a function of pH and the corresponding thermal and photostabilities dramatically increased compared with its solution sample. 相似文献
1000.
Yasushi Nishihara Eiji Inoue Daisuke Ogawa Yoshiaki Okada Shintaro Noyori Kentaro Takagi 《Tetrahedron letters》2009,50(32):4643-4646
The palladium-catalyzed cross-coupling reactions of aryl iodides with alkynylsilanes in the presence of a substoichiometric amount (50 mol %) of copper(I) chloride as an activator in DMF under strictly non-basic reaction conditions afford the corresponding unsymmetrical diarylethynes in moderate to excellent yields. A wide range of substrates bearing an electron-donating or an electron-withdrawing substituent on the aromatic ring are compatible. 相似文献